The problem with cam spec's is most of them are not correct to begin with. You have to know how the camshaft is designed and most haven't a clue. People look at intake closed from a cam card and think that tells them lots about a cam and it does not! That works about as well as pi$$ing into a 50 mph wind and hoping you do not get wet!

Take yourself a piece of paper out and draw three horizontal lines on the paper the first two about 1/4" apart and the third line about 1" above the second. This gives you the three point on a the camcard for a lobe design. Base circle is the bottom line, the second line is the 0.053" line and the third line is peak valve lift. Now the other thing that's on a cam card are what is called valve opening and closing points but neither are correct for when the valve opens or closes. What they are is a point when the lifter has moved 0.053" from the base circle. No where on a cam card does it show you how the lobe is designed, which is the most important part of it.

So now you take the middle point on the third line and place a dot in the center of the line and that's your peak valve lift point from the cam card. Now go to the left of that dot you placed on the third line and drop down to the second line and put a new dot about 1/2" to the left of the peak lift dot on the second line, That's your camcard open point. Do the same for the close point but move to the right 1/2" from the valve lift point and put the dot on the second line again. Now what you have are three points in space from your camcard. No where on a camcard does it give you any information how to start from the base circle (bottom line) to get to the second line (0,053" point) or how to get to the third line! Same goes for coming back down on the closing side points. So it is very possible for thousands upon thousands of ways to draw lines and connect the three dots! All of those designs will have the exact same spec's but will perform very very differently when installed in an engine.



Here I've drawn just two lines that meet the exact same spec's but are worlds apart in how they will perform, and as anyone can see there are plenty more lines that can be drawn through the same three points, so what does a cam card really tell you? Now the more aggressive you design on the opening side, the valve train gets nosier and it will have a short life span and on the closing side it beats the hell out of the valves and seats but is commonly done on many camshafts used in the HD world. So this is why we do not want to get into the pi$$ing match with cam card specifications. We by design, make camshafts that are made to be easy on parts and are designed for at least a 50,000 mile service life. By living with those requirements it limits some of the things we can do, but we are not after a race engine with high compression that you cannot ride across the USA two up and loaded.

If that's what your looking for we are not what you want.

 

Like Your read Mr. Cole.. It's kind of the difference between the say the twincam old woods W-8 and Andrews 55. Andrews has lower lift and nicer ramps but the W-8 can do much better. The W8 needs roller rockers to keep from scuffing the tops of the valves.

 

Kinda like the difference between a triangle and a rectangle.

 

And everything in between!

 

Remember fellers, I'm NOWHERE as sharp as you guys, but I'm learning a ton right now! Thanks to all and Steve!

So, where I'm at, at this point, is we know we're going to bore out the OEM 103 cylinders like .010" - .015" over, or more if we HAVE to, but hope not. Going with flat top pistons, (either JE or Wiseco), with about 10.5:1 compression. (Just like Gunner thought I might get earlier in the thread).

Getting the heads worked with larger valve sizes, (can't remember exactly what size at the moment, but I'll find out for sure on Monday.) Also doing a little grinding on the heads to help the flow and get rid of the "Step" in there. Putting in some Beehive springs and my buddy was mentioning maybe roller rockers, but I'm not positive on those at the moment. I don't have anything against them, but I just need to know more.

As mentioned before, I already run the V&H Power Duals, (2-1-2), 4" Slash Cuts, and Arlen Ness Monster Sucker, Andrews 48H cams with the TTS tune.

So, knowing my riding style, (95% two up, and 70% of that also with luggage/gear, for those that didn't read the whole thread, lol), a lot of two lane when possible, but super slab when needed to get to the right coast and back to the left coast. Looking for the low end grunt coming out of twisty hairpins with Mrs. MJ on the back while riding through the switchbacks in my local Sierra mountains, the Rockies, Appalachians, etc.. Ride anywhere from -250' to 12,000' elevation on any given trip.

All that being said, I'm really kind of interested in @Steve Cole 's 100 or 150 cam to go along with my TTS tune that Bob from RC Cycles in Hayward will be doing. I like the idea of not beating up my drive train and hopefully making it a little quieter at the same time. What do you guys think? Does this sound like a solid setup for my riding style? If you have a serious dislike for TTS cams, be very clear as to why you don't think I should lean into that........... I'd be interested in your opinion.

TIA ya'll!

MJ

 

I doubt you will find any valid reasons NOT to do TTS cams except ignorance.
Since you are bumping compression, the TTS 150 would be a better choice. They will carry out further AND still have good low end torque.
Of course there are a few others that would do well at 10.5 too and they don't start with a W.
I've been saying the same thing about cams. The intake valve events on a cam card are often misleading and just because two cams have identical intake open/close doesn't mean jack. There's more to a cam's caracteristics that aren't even on a cam card.
Case in point, the Tman 590 and woods triple 8. The 590s will outperform every time. I've seen it more than once. Both have intake valve events of 23/43.

When you start getting outside of this forum, you will start to see what's popular here means very little. This next comparison will show that and what TTS cams and some other less "popular" cams are capable of that the popular cams here are not.
These are m8 cams but shows what I'm talking about. The 175 has just as much low end but gradually and consistently walks away from 3000rpm up. This is what I like about TTS cams and others like them. Yet you seldom hear about TTS cams here and Woods cams are pushed to the point of sickening. It's a popularity contest here with some good knowledgeable threads thrown in now and then . Nothing more.
When this was first posted here, I think one or two people commented about it and it quickly died.
So the question is, do you want popular? Or the best cam for the job?


https://www.google.com/imgres?imgurl...p2eXsczQVZuonM

 

Got the receipts?

Not sure why you posted M8 stuff. Cam timing different between bikes.

 

It doesn't surprise me the point went right over your head and the receipts are not mine to keep. You keep pushing your woods cams, Max. I wouldn't expect anything different from you even tho you know it as well as I do.
Gotta go watch my grass grow, now.
We melted 2 feet of snow this past week.
I have a 2000 Nightrain tore down waiting for warmer weather to build to make room for a couple shovels and HD golf carts to tune up and I'm not heating the garage.
Besides, I need my free time right now to recover every week from a work week with UAW local 94. I'm too old for that **** but the $$$ and bennies are too good to pass up. Its a killer pace but when CIPP pay is like 145% of a base of $30.00+...well you do the math. Our line has some money hungry people. Rate is 42 units a day for skidsteers built to perfection. We were done by noon and sat there til 2:30 quitting time surfing the net on our cell phones. Every day. It's insane.

 

And.......... not to derail my own thread, but it is MY thread so I guess I can, lol......... what about increasing the TB size from 50mm to 55mm as well as taking the injectors from 4.3 gr/s to 5.3 gr/s? With the increased valve sizes, would this be beneficial, or a waste of $$$?? I don't have an issue with spending the money if it will help, but why waste it if it's not really gonna do anything for the build.

 

You really need to choose a cam first before deciding things like valve sizes/compression, etc. Valve size, specifically intake to exhaust ratio and TB size is important and cam duration and pipes make a difference in the best valve sizes.
I'm partial to the HPI Max Flow TB. Smaller TB with a slightly bigger plenum. Like 55/58.
But again, TB size depends on how the heads flow.
But yes, a 55mm would be better than the 50mm where you're headed and 4.9 injectors big enough but 5.3 wouldn't be too big and there is such a thing as too big.

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